String



June 28, 1932. 1 SALADlNO ET AL 11,865,24

STRING Filed Jan. 26, 1931 Fatented June 28, 193

JOSEPH SLADINO AND SALVATORE SALADINO, OF CHELSEA, MASSACHUSETTS, AS-

SIGNCRS TO C. SALADINO t SONS, INC., 0F CHELSEA., MASSACHUSETTS, A CORPORA- MON STRING? Application led January 26, 1931. Serial No. 511,313.

This invention relates to strings for tennis rackets, musical instruments, belt lacing, surgical sutures, looms, and other purposes.

At present these strings are made of gut') 5 alone, or silk alone, no successful combination of silk and gut having been achieved, although we are well aware that others have unsuccessfully attempted to combine silk and gut in a string which would be acceptible to the trade.

With respect to such uses as for stringmg of tennis rackets, gut has the desired resiliency, but not the desired tensile strength for long wear, and its cost is too great; while silk has the desired tensile strength and its cost is reasonable, but it lacks resiliency.

Consequently either an all gut string or an all silk string is objectionable in one or more important respects.

One of the objects of our invention is to so combine silk and gut that a string may be made from a combination of the two which has the desired tensile strength and resiliency, the cost of which is materially less thany of an all gut string. Another object is to devise a time and labor saving method to produce such a combined silk and gut string. U

rlhe foregoing and other objects which will appear as the nature of the invention is better understood, may be accomplished by a combination and arrangement of elements and by a method herein disclosed and shown in the drawing. The nature of the invention 5 is such as to render it susceptible to various changes and modifications, and therefore, we are not to be limited solely to that which is disclosed by the specification and drawing; but are entitled to all such changes there- 0 from' as fall within the scope of our claims.

fn the drawing: Figure ,l is a longitudinal section through the receptacle containing 'the compound with which the strings (shown enlarged) are treated, and also showing devices over or throughwhich said strings pass just before and just after being treated.

Figure 2 is a side elevation of a drying rack showing the strands (shown enlarged) 0 of gut connected to a twisting device and ready to be wrapped around a core consisting of silk strands (shown enlarged).

Figure 3 is a side elevation of the dryin rack and twisting device showing finishe strings on the drying rack.

Figure 4 is an enlarged fragmentary view of a nished string, and shows that both the gut and silk core have been twisted.

fn practising our invention we find it preferable to use animal gut, either whole or split, particularly the intestines of sheep, and genuine Ysilk from the silk worm, although the use of fibrous materials such as hemp, linen, etc., and artificial silk commonly called rayon, is possible.

The strands of gut should be given the preliminary and well known treatments to clean it, remove thebacteria contents, fats, et cetera, now commonly given gut strings, and while still wet it is treated by dipping or running them through a compound, for which compound a patent application filed by us and Frank Saladino is now pending, Serial No. 510,056, filing date January 20, 1931. The strands of silk to be used, which require no preliminary treatment, should likewise be treated by dipping or running through said compound. This important treatment renders the silk and gut moisture proof, im arts adhesive qualities, and makes a glossy nish possible. Said compound is made of water, gelatine, red beef oil distilled,` glycerine and tallow oil, and it is preferably prepared in proportions and by steps as follows:

Three pounds of gelatine in one gallon of water are cooked to a temperature of approximately 200 degrees Fahrenheit, then one ounce of red beef oil distilled is added and thoroughly stirred in, after which five ounces of glycerine (glycerine for commercial purposes is suitable) are added and stirred in, followed by adding five ounces of tallow oil and again stirring, keeping the temperature at approximately 200 degrees Fahrenheit while adding these various ingredients. If coloring is desired it should be added next and stirred in, using a water dye of the desired color, maintaining said temperature.

Said compound should be maintained at a constant temperature of approximately 200 degrees Fahrenheit while the strings are run through it or dipped into it. In the manufacture of strings having a silk core with gut wrapped around which we disclose, this compound is not absolutely necessary for treating said strings, as even if not treated they would be useful although inferior to a treated string.

The strands of gut or silk may be dipped in said compound by hand, immersing them only for a very short time-usually less than a minute-just long enough to be sure the strands are covered with the compound. If split gut is to be used the splitting should be done prior to this treatment. The gut strands should be dipped in a different receptacle containing said compound than the silk strands, for the moisture in the gut tends to weaken the compound and oftentimes it has to be thrown away on account of becoming too weak, whereas the silk does not weaken the compound at all.

In place of hand dipping however we have found it more advantageous to draw or run the silk or gut strands through a receptaclel containing the compound, using the devices shown in Figure 1 of thel drawing, in which 12 represents either the silk or gut strands, 13 the spool around which it is wound. v Said spool 13 is supported by brackets 14 and said strands 12 travel through an eye 15 to a roller 16, then under and over the tensioning roll-v ers 17 and through another eye 19. Said elements 14, 15, 16, 17 and 19 are supported or mounted on a box frame 18. Said strands pass through an aperture 2O made in the side of the inner or compound container 21 which is enclosed by an outer or hot water container 22. The treating compound C should be kept at a temperature of approximately 200 degrees Fahrenheit, consequently hot water W in said outer container 22 must bemaintained at a sufficiently high temperature to keep the compound C at said temperature, and a heating unit 28 may be utilized to supply the necessary heat.

Within the inner container 21 are rollers 23 completely immersed in the compound under and over which said strands 12 pass upwardly through a well known wiping device 24 and out through the top 25 of said inner container. Thence they run through equalizing rollers 26 which squeeze the surplus compound out, distributing and equalizing the remainder in the strands. Said strands then pass over guide roller 27 and a ...-0 loop 30 of string or rope is tied onto the end of said strands 12 in order to hang them on pegson the drying rack or fasten to a hook on a twisting device later described. The number of strands of silk whichwill form a single core should be run through together so that after said strands have been treated they may be hung up on the racks to dry almost asa unit, ready .to have gut twisted around them later. Likewise the number of gut strands necessary to properly wrap one silk core should be run through practically together, and they appear to be one unit 12 in the drawin s although they are not twisted or otherwise bound together during this stage of the process. Ordinarily thirty-eight strands of silk and fourteen strands of split gut are used to make a fifteen gauge tennis string, or if whole gut is used seven strands are sutlicient'. The number of strands will vary, of course, depending upon the size of the strands, gauge and type of string desired, etc. Sucient gut should be used to completely cover the core of silk, and very satisfactory results have been obtained where the total weight of the silk is about equal to the total weight of the gut.

Said drying rack consists of vertical supports 31 and horizontal supports 32, in which 'vertical supports, pegs or protruding arms 33 are inserted. The holes to accommodate said pegs are made in various positions as shown in Figures 2 and 3 of the drawing to accommodate the different lengths of strings to be hung thereon. Said drying rack also has intermediate supports or turn buckles 34 for purposes of rigidity.

After the treated strands of gut and silk have dried, a length of silk 37, which contains suiicient strands to serve as a core in the finished string, is fastened at one end by the loop 30 to a peg 33 in said drying rack, and a length of gut strands 36 is fastened to said loop 30, said silk 37 is on the other ends of silk 37 and gut 36 being fastened by another loop 30 to a hook 38 mounted on a well known twisting machine 39. As will be noted in Figure 3 of the drawing said length of gut 36 is longer than said silk 37, on account of the extra gut needed for wrapping. For instance, a silk core twenty-one feet long requires a length of gut about twenty-two and one-half feet long, in order to wrap and cover all of said silk.

Said twisting machine 39 is preferably motor driven, and upon being set in motion said length of gut strands 36 is wrapped around said silk core 37 as both are twisted. After this wrapping the string is hung up to dry for a period of one hour or more, depending a great deal upon climatic conditions and the temperature of the room.

After being suiiiciently dried said string is hooked at one end to a peg 33 and at the other end to said twisting device hook 38 and the device is again set in motion twisting said string until the desired firmness is attained which is readily determined by a skilled operator through the senses of touch and sight. Said string 40 is again hung on a drying rack and driedb and usually it is necessary to repeat said twisting and drying two more times, the number of twistings depending a. great deal upon climatic conditions as all -moisture should be removed from the string all sag taken out, and it should have the appearance of a solid one-piece string.

The number oit' twisting operations together with the extent of the twisting in each operation is determined by the operator who is skilled in this work, and this is now a well known practice in the manufacture of all gut or all silk strings.

Said iinished length of string is now moisture proof and is ready for the well known linishing process after some mineral oil is applied as is now customary.

The use of silk and gut treated with this compound makes it possible to twist the strings as tightly as desired, which we are unable to do with gut alone on account of its lack of suiiicient adhesiveness and tensile strength. The silk core serves as a rebound when playing tennis, and the gut has its natural resiliency, with the result that in tennis play our strings combinesubstantially all the advantages, which both silk and gut have when used alone.

An all gut string in a tennis racket or musical instrument, etc. slackens after being strung; but with a silk core this is eliminated, for the silk core will not permit the slackening.

What weclaim is:

l. A string comprising a plurality of strands of fibrous material forming a core, and a plurality of strands of gut covering said core, said string being in twisted cony dition.

2. A string comprising a plurality of strands of silk forming a core, and a plurality of strands' of gut wrapped around and covering said core, said silk and gut being in atwisted condition.

3. A string comprising a plurality of strands of silk forming a core` and a plurality of strands of gut wrapped around said core, ,said strands embodying a moisture proofing compound.

4. A twisted string comprising a plurality of strands. of silk forming a core, and a plurality oi. strands of gut wrapped around said core, said strands embodying a compound. which has imparted moisture proof and adhesive qualities to said strand.

5. A finished string comprising gut and a material of less resiliency than said gut forming a core, said gut covering said material.

6. A finished string comprising gut and a material of less resiliency than said gut forming a core, said gut being wrapped around and twisted with said material.

7. A string comprising strands of gut and strands of material f less resiliency and of greater tensile strength than said gut, said gut being wrapped around and covering said material, and twisted with it.

8. A string comprising a plurality of strands' of silk forming a core, and a plurality of strands of gut wrapped around said core, the whole having been so treated and twisted to such a degree of firmness that said string appears to be composed of one piece of mafina 

